Which of these is the measure of an obtuse angle?
A)45 degree
B)90 degree
C)120 degree
D)180 degree
My answer is 120 degree.
Right.
The measure of an obtuse angle is greater than 90 degrees but less than 180 degrees. To determine which of the given options is the measure of an obtuse angle, we need to compare each option to 90 degrees.
Option A) 45 degrees: This angle is less than 90 degrees, so it is not an obtuse angle.
Option B) 90 degrees: This angle is exactly 90 degrees, so it is not an obtuse angle.
Option C) 120 degrees: This angle is greater than 90 degrees but less than 180 degrees, so it is the measure of an obtuse angle.
Option D) 180 degrees: This angle is equal to 180 degrees, which is a straight angle. Straight angles are not considered obtuse angles.
Therefore, the correct answer is C) 120 degrees.